diff options
Diffstat (limited to 'gcc/config/avr/avr-passes.def')
| -rw-r--r-- | gcc/config/avr/avr-passes.def | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/gcc/config/avr/avr-passes.def b/gcc/config/avr/avr-passes.def index eb60a93..d668c7f 100644 --- a/gcc/config/avr/avr-passes.def +++ b/gcc/config/avr/avr-passes.def @@ -74,6 +74,14 @@ INSERT_PASS_BEFORE (pass_free_cfg, 1, avr_pass_recompute_notes); INSERT_PASS_AFTER (pass_expand, 1, avr_pass_casesi); +/* Insn combine may come up with superfluous reg-reg moves, where the combine + people say that these are no problem since reg-alloc is supposed to optimize + them. The issue is that the lower-subreg pass sitting between combine and + reg-alloc may split such moves, coming up with a zoo of subregs which are + only handled poorly by the register allocator. */ + +INSERT_PASS_AFTER (pass_combine, 1, avr_pass_2moves); + /* Some combine insns have nonzero_bits() in their condition, though insns should not use such stuff in their condition. Therefore, we split such insn into something without nonzero_bits() in their condition right after |